Sulphophthalic acid derivatives reaction products of fatty alcohol C12-C14 and sodium hydroxide

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May from 07 to 12, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

adopted July 27, 1995

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

Test Item was used in its initial form.

Melting / freezing pt.:

-28.8 °C

Decomposition:

no

MAIN TEST

During the cooling down phase of the DSC runs one exothermic peak was observed at ca. 0 °C, attributed to the freezing temperature of the water content of test item. During the cooling/heating phases at ca. -29 °C glass transition was observed which was assumed the freezing/melting point of test item. Midpoint ISO temperature was used for the calculation of the mean freezing/melting point.

	Experiment Phase	Sample weight [mg]	Onset of effect [°C]	Midpoint ISO [°C]	Mean Midpoint ISO [°C]
Exp. 1	Cooling down	3.39	-26.53	-27.82	-28.90
	Heating up		-30.18	-29.97
Exp. 2	Cooling down	6.86	-26.49	-27.51	-28.72
	Heating up		-30.12	-29.92

Before the test the appearance of the test item was yellow liquid. After the experiments the test item became black, porous and its volume increased in the crucible.

PRELIMINARY TEST

Observations during the freezing point test

Temperature (°C)	Storage period (hours)	State of the samples
		Replicate 1	Replicate 2
-30	24	solid	solid
-30	48	solid	solid

Conclusions:

The melting/freezing point of the test item was determined to be -28.8 °C.

Executive summary:

The thermal behaviour of the substance was investigated using the Differential Scanning Calorimetry method, according to the OECD guideline 102.

In order to check the approximate freezing temperature, 1 ml of the test item was transferred into 2 ml cryovials. Four replicate tubes were placed in the freezer (-15 to -30 °C). After at least 24 hours storage period two replicate tubes were removed and the physical state of the test item was examined. The test item was frozen in the tubes, therefore the main test was conducted.

A small amount of test item was weighed into a one-way 40 µl aluminum crucible and sealed with pierced aluminum lid using a capsule presser. Thus prepared capsule was inserted into the furnace of the DSC device and cooled from room temperature to -40 °C with 0.5 °C/min cooling rate and then heated again to room temperature with 0.5 °C/min heating rate. The measurement was performed under nitrogen atmosphere and the experiment was performed in duplicate.

Before the test the appearance of the test item was yellow liquid. After the experiments the test item became black, porous and its volume increased in the crucible. Before the test the appearance of the test item was yellow liquid. After the experiments the test item became black, porous and its volume increased in the crucible.

Conclusion

The melting/freezing point of the test item was determined to be -28.8 °C.

Description of key information

The melting/freezing point of the test item was determined to be -28.8 °C.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-28.8 °C

Additional information

OECD 102 - Differential Scanning Calorimetry method